I was rebuilding my 2 barrell carb and I started to tighten the power valve on the bottom of the carburetor when it snapped. I took it out and showed the parts store where i bought it and told him I think it was defective because i did not tighten it tight and it snapped and he told me they are pot metal you don't really tighten them up little more than hand tight.  I told him the old one tightened up fine but he charged me for a new one 9.00. I would like to know what is the correct torque on them so I do not have to buy another new one.  

Timmy:

Some power valves have four rectangular windows between the threaded portion and the gasket surface, some have four small drilled holes.  Obviously, the window type is much weaker.  Sorry, I can't tell you the torque value, but with the window type you have to be careful.  They are not under pressure, so don't have to be real tight.

John in Selma, IN

John - "The Hoosier Hurricane"